ffmpeg - How can I extract the image included in the MJPEG stream of an MKV file?

Question

I have a video file, and when I describe it using the ffmpeg -i command, I see the following:

Stream #0:4: Video: mjpeg (Baseline), yuvj444p(pc, bt470bg/unknown/unknown), 540x800 [SAR 1:1 DAR 27:40], 90k tbr, 90k tbn, 90k tbc (attached pic)
filename : cover.jpg
mimetype : image/jpeg

What is the ffmpeg command line to extract the cover.jpg image that is apparently contained in this stream?

I have tried the -dump_attachment:t option, but I don't think it applies here and in any case, it did not work.

Answer 1

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